1. Field of the Invention
The present invention relates generally to an information terminal, such as a notebook-sized personal computer (PC), etc., and keyboard and system units thereof, and more particularly to an information unit in which a keyboard unit can be readily mounted in a system unit, and the keyboard and system units thereof.
2. Description of Related Art
A keyboard in a notebook-sized PC, in addition to being one of the input devices, structurally functions as one of the covers and also functions as a shield plate for intercepting external noise and electric wave noise emitted from the device itself. Because of this, a base plate (usually made of metal) constituting the keyboard unit must be electrically and mechanically connected with reliability.
Similarly, as the keyboard may or may not be provided with a system unit, it is known to provide a keyboard with a removable connection such that a keyboard may be removed, repaired, replaced, or substituted with another input device as a particular function may require.
For instance, it is often necessary to mount a keyboard unit according to the language that is employed in the specific country in which it is to be used. Additionally, it may also be more efficient to previously assemble a system unit excluding a keyboard (semi-finished product), mount a keyboard unit while having a keyboard on order, in the semi-finished system unit, and ship the finished product in a very short time. Further, often there exists the danger that a keyboard will be subjected to damage simply when used in normal operation given the environment in which it is used (e.g., such as a case where coffee is spilt on the keyboard, or where a heavy item could fall on the keyboard).
Thus, it is necessary to provide for the situation where a user can replace a keyboard unit when it fails.
However, since keyboard units may also be connected with a speaker, an audio card, audio jacks (e.g., a headphone and a microphone-in), etc., a method of mounting and dismounting the keyboard unit so that it can be reliably carried out even by users having no skill, while ensuring the integrity of the electrical and mechanical connection, is desired.
Thus, the keyboard unit has various important roles. However, mounting of the keyboard unit into the system unit is usually performed by placing the top surface of the notebook-sized PC downward, then driving a plurality of small screws into the bottom surface, and mounting the keyboard while it is being pulled downward. Because of this, there is often a problem in that the keyboard unit cannot be easily mounted in the system unit.
An object of the present invention is to provide an information terminal and keyboard and system units thereof, which are capable of making mounting of the keyboard unit into the system unit easier while reliably providing for electrical and mechanical connections, while eliminating the problems mentioned above.
The information terminal of the present invention is equipped with a keyboard unit detachable with a system unit. The keyboard unit is equipped with (a1) a base plate, (a2) a keyboard-unit-side engaging member, disposed on the bottom surface of the base plate, for detachably engaging with the system unit, and (a3) a plurality of input keys disposed on the top surface of the base plate opposite to the bottom surface on which the keyboard-unit-side engaging member is disposed. The system unit is equipped with (b1) a system-unit-side engaging member for detachably engaging with the keyboard-unit-side engaging member.
In the information terminal of the present invention described above, the keyboard unit can be mounted in the system unit only by engaging the keyboard-unit-side engaging member with the system-unit-side engaging member.
In a preferred embodiment of the information terminal of the present invention, the keyboard-unit-side engaging member is a hook button. Also, the system-unit-side engaging member is a hairpin spring. In addition, the keyboard unit is mounted in the system unit by fitting the hook button into the hairpin spring. In the preferred embodiment, the keyboard unit can be easily mounted in the system unit by fitting the hook button into the hairpin spring. Also, electrical and mechanical connection can be reliably performed between the keyboard unit and the system unit. For that reason, easy assembling, prevention of the floating of the keyboard (particularly, the central portion), and strengthening of an EMI radiation countermeasure and ground for ESD and RF can be achieved when mounting the keyboard unit into the system unit.
In another preferred embodiment of the information terminal of the present invention, the hairpin spring is positioned toward the keyboard unit so that the keyboard unit is pulled toward the system unit, with the hook button fitted in the hairpin spring. This preferred embodiment makes the electrical and mechanical connection of the keyboard unit with the system unit more reliable. Particularly, this preferred embodiment is capable of effectively preventing floating of the keyboard.
In another preferred embodiment of the information terminal of the present invention, a portion of a front end portion of the base plate of the keyboard unit is engaged with a groove provided in the system unit. Also, the hook button is fitted into the hairpin spring. Furthermore, at a rear end portion of the base plate of the keyboard unit, the base plate is screwed to the system unit. In the third preferred embodiment, screwing becomes necessary, but the number of places to be screwed can be reduced compared with the related art. Also, the screwing operation can be performed through the top surface of the system unit, and simple mounting can be maintained. In addition, the keyboard unit can be firmly connected electrically and mechanically to the system unit.
In another preferred embodiment of the information terminal of the present invention, two tip portions of the hairpin spring are fixed by a pin base. Also, the hairpin spring is provided at each of two positions on the system unit which are symmetric with respect to a center of the base plate. Furthermore, the base plate is made of aluminum, the hook button is made of brass, the hairpin spring is made of stainless steel, and the system unit is made of Carbon Fiber Reinforced Polymers (CFRP). CFRP have low specific gravity, excellent mechanical properties (high specific tensile strength, high specific elastic modulus. etc.) and preferred performance characteristics (electric conductivity, heat resistance, low thermal expansion coefficient, chemical stability, self-lubrication property, high heat conductivity, etc.) for the present invention. Similarly, it will be further understood by those of ordinary skill in the art that various changes in the details, materials, and arrangements of the parts which are described and illustrated herein in order to explain the nature of this invention may be made by those skilled in the art without departing from the principle and scope of the invention as expressed in the following claims, and as such, the above referenced and additional envisioned embodiments are capable of effectively achieving the present invention in a variety of ways.
The keyboard unit of the present invention is generally constructed so that it detachably engages with a system unit of an information terminal. The keyboard unit is equipped with (a1) a base plate; (a2) a keyboard-unit-side engaging member, disposed on the bottom surface of the base plate, for detachably engaging with the system unit; and (a3) a plurality of input keys disposed on the top surface of the base plate opposite to the bottom surface on which the keyboard-unit-side engaging member is disposed.
Furthermore, the system unit of the present invention is configured to detachably engage with a keyboard unit which includes a base plate, a keyboard-unit-side engaging member, disposed on the bottom surface of the base plate, for detachably engaging with the system unit, and a plurality of input keys disposed on the top surface of the base plate opposite to the bottom surface on which the keyboard-unit-side engaging member is disposed. The system unit is equipped with a system-unit-side engaging member for detachably engaging with the keyboard-unit-side engaging member.
The keyboard and system units of the present invention described above can be satisfactorily used in the information terminal of the present invention when mounting the keyboard unit into the system unit.